Al Leslie

Al Leslie is an immunologist whose research focuses on the immunopathology of tuberculosis (TB) and HIV. He leads a research group at the Africa Health Research Institute (AHRI) that studies host–pathogen interactions within tissues, particularly in the lung during TB infection.

His work investigates both innate and adaptive immune responses using techniques such as flow and mass cytometry, histology, and RNA sequencing. This has helped reveal tissue-specific mechanisms of protective immunity and disease pathology that are not apparent from blood-based studies alone.

His group also develops and uses 3D granuloma models to study TB infection in tissue-like environments, with the goal of identifying targets for host-directed therapies and biomarkers of disease progression. These biomarkers are further evaluated in blood and sputum samples using clinical cohorts in Durban and AHRI’s population research platforms in rural KwaZulu-Natal.

In addition to TB, his research examines how HIV infection affects immune responses in tissues, including the gut and secondary lymphoid organs, highlighting that HIV has more profound tissue-level effects than can be detected through blood-based analysis alone.